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Stringent design specifications for out-of straightness during pipe-lay operations for depth of cover measurement are becoming more important with the increase in the development of high temperature and high pressure fields where smaller diameter subsea flowlines are specified. One such project where out-of-straightness and cover heights are of particular importance to pipeline stability is the Norsk Hydro Troll West field development in the Norwegian sector of the North Sea. Here a hydraulically operated ROV (remotely operated vehicle)-based mechanical stabbing system has been used. Conclusions are drawn on the effectiveness potential benefits and accuracy of Inertial Geometry Surveying for both depth of burial backfill cover and out-of-straightness and excessive curvatures. This is followed by some 4 pages of graphs.

An exciting addition to the "Horrible Histories" series, these titles will tackle all the hot historical topics in a new full-colour format with durable cover. Beginning with the perennial favourite Pirates, Terry Deary reveals the terrible truth behind the lousy pirate legends and lies. So forget the brave heroes swinging from masts and the handsome young men sailing the seven seas for this is history as it's most horrible! Readers can decide who was the baddest of the bunch in the top ten of putrid pirates, discover why the women pirates were just as wicked as the men and learn to talk the patter of a Pirate. Plus there are foul facts on the ships they sailed, the punishments they suffered and the rules they lived by. Now the nasty bits are at your fingertips! 10 yrs+

The planning stage of a high-pressure high-temperature (HPHT) well to be drilled in the Santos Basin offshore Brazil is described. The planning began with visits to other HPHT fields and a study of a failed HPHT well in the same region of the Santos Basin. A detailed well plan was then produced that took account of all foreseeable eventualities and a rigorous specification was made to contract a semi-submersible to drill the well. Previous problems were focused on well testing so special care was given to this particular factor. It is concluded that the effort spent at the planning phase was key to the success of the drilling phase. Details of the plan the drilling and the testing programme are given.

Summarised results of a study into a simplified method for the design of thick icebreaker shell plating subject to realistic highly concentrated impact loads are presented. The method allows permanent set or the permanent set to frame spacing ratio to be used as the response criterion. A design method was hypothesised based on theories which transform concentrated loads into equivalent uniform loads and which allow plate thickness to be related to the permanent set criterion. The analytical approach its validation using realistic ice impact loads and the finite element model and the resulting design method for icebreaker shell plating are presented.

The analytical formulation and numerical simulation of the control of an OWC (oscillating-water column ) power plant is presented. PMP (Pontryagin Maximum Principle) is applied to an OWC with a throttle valve - latching control is allowed. It is assumed that the rotational speed for the turbo-generator set is variable and thus a control strategy for the generator is taken into account. It is also assumed that the plant has a by-pass valve that prevents aerodynamic stall at the turbine rotor blades. The control aims to maximise the amount of energy delivered to the generator taking into account not only the hydrodynamic performance of the device but also the aerodynamic performance of the turbine and bypass valve. It should be noted that this performance depends on the rotational speed of the turbo-generator set and thus it is related to the control strategy applied to the generator. A wave-to-wire model that includes the two control strategies (generator and throttle valve control) is devised.

The importance of larval dispersal to the population dynamics and biogeography of marine organisms has been recognized for almost a century. However few empirical estimates of larval dispersal or population connectivity in ocean environments exist. However ecologists have embraced recent developments in probe-based mass spectrometry to examine the chemistry of calcified structures in marine invertebrates and fishes that can be used as artificial or natural tags of natal origins. These geochemical tags are revealing fascinating data on larval dispersal that are chellenging widely held paradigms concerning the spatial scale of demographic connectivity in ocean ecosystems. A look is taken at geochemical approaches and progress to date. Next consideration is given to emerging technologies and future directions followed by implications.

Degradation to the flexural strength and stiffness of glass reinforced polyester (GRP) ship panels due to fire is investigated in this paper. Large GRP panels were exposed to a kerosene fuel tray fire with an average temperature of 300°C for different times up to 10 minutes to simulate exposure to a shipboard fire. The extent of fire damage to the panels increased with exposure time and the two main types of damage were charring (due to combustion of the polyester resin matrix) and delamination cracking. The residual flexural properties of the fire-damaged panels were determined at room temperature by loading to rupture in four-point bending. The flexural stiffness and strength decreased rapidly with increasing exposure time due to the spread of fire damage through the composite. Rule-of-mixtures models based on a reduced area of effective material due to the fire damage are presented for predicting the residual flexural properties of fire-damaged GRP ship panels.

The objectives of the book are to discuss in some depth the wide range of technologies that are involved in power circuit breaker design. Chapters have been written by eminent engineers concerned with circuit breakers, in areas that are of special interest to them. Therefore chapters cover defined subjects - these are: circuit breaker arcs; network switching conditions; oil circuit breakers; air-break circuit breakers; air-blast circuit breakers; sulphur-hexafluoride (SF6) circuit breakers; vacuum circuit breakers ; special switching systems; circuit breaker specification and testing; design criteria for reliability, maintenance and safety; insulation applied to circuit breakers and; cost-effective design.

Several recent and anticipated developments in marine electrical system engineering must be considered in the context of power system protection. These include: the introduction of large-scale IFEP (Integrated Full Electric Propulsion) systems where the role reliability availability and survivability of the power system have become more critical than before; the introduction of hybrid ac/dc power systems and power-converter interfaces which have a strong influence on the behavior of the overall system; increased requirements for redundancy and automatic power system reconfiguration particularly in military applications where security of supply and continued operation in battle-damaged modes is essential; the introduction of loads such as EMALS (Electro-Magnetic Aircraft Launch System) and advanced weapons systems which often require conditioned power supplies. Such developments present a number of issues and challenges associated with the protection of the power system; these issues and potential solutions are discussed in this paper. Requirements for further research are also presented.

Wave energy converters are very often tuned to suit the more frequent significant wave period of the project site. In this paper an attempt is made to show that optimizing the device necessitates to account for all possible wave conditions weighted by their occurrence frequency as generally given by the classical wave climate scatter diagrams. Instead of a real device a generic and very simple wave energy converter is considered here. It is shown how the optimal parameters can be different considering whether all wave conditions are accounted for or not whether the device is controlled or not whether the vertical motion is limited or not. It is also shown how they depend on the area where the device is to be deployed by applying the same method to three very different sites.

Recent international towing tank conference committees have discussed powering prediction methods for ships fitted with unconventional propulsors. The difficulties arise in powering prediction for these vessels because of the strong interaction between the propulsor components and the flow around the hull. Powering prediction methods using a combination of results from resistance propulsor open water and self-propulsion tests can lead to errors and uncertainty in powering prediction and incorrect trends in performance with increasing Reynolds number. With this in mind the prediction of full-scale ship-powering performance from model load-varying test data is discussed. The methods concentrate on using the load varying tests in isolation of resistance and-or propeller open water tests. Values of a form factor a resistance and a thrust deduction fraction are found from an analysis of the under- and overload tests. The full-scale torque and thrust coefficients are estimated from the model propeller data in the behind condition. The method is illustrated by using model test data for two twin-screw vessels for which corresponding full-scale trials results are available. The results are compared with an extrapolation done using the ITTC 1978 method.

The methodology of study carried out on a 130000m3 gas carrier built by Chantiers de l'Atlantique to work out the ship's main natural frequencies in order to try excluding resonance phenomenon risk is described. A global 3-D finite element analysis was done. Vibration measurements were carried out with the help of an unbalanced exciter during construction (as soon as the vessel was floating) and before and after sea trials. Further vibration measurements for different RPM confirmed the correlation between predictive analysis and the vessel's actual behaviour at sea. Lastly an experimental simple active system to reduce a peak of resonance was carried out.

A ship is continuously in motion during running in waves. The main reason for such motion the wave exciting force and moment acting on a ship. Among various motion modes such as surge sway heave roll pitch and yaw roll influences mainly the cargo safety and passenger comfort in conventional displacement- type vessels. In order to reduce the roll of a ship in waves anti-rolling stabilisers are used. Anti-rolling tanks moving weight stabilisers and fin stabilisers are typical anti-rolling devices. Amongst these fin stabilizers are the most effective for a ship running at normal speed. The solution for disturbance dominant problems such as roll stabilisation of a ship in waves can be the predictive control algorithm. In this study a predictive control algorithm was developed for a fin stabiliser.

Using optimisation methods preliminary ship design is a multi-disciplinary task that aims to identify basic ship dimensions and corresponding performance measures that maximise a set of design objectives. The process involves a search through a large variable space in the presence of highly non-linear constraints arising out of user requirements statutory norms and physical laws. The focus of this paper is the application of a 'new' evolutionary solver to an existing model with the outcome being better results. A multi-objective evolutionary algorithm that is capable of effectively and efficiently solving single or multi-objective unconstrained or constrained optimization problems with mixed variables is used. The underlying algorithm relies on a stochastic population-based elitist zero-order model which explicitly maintains diversity of solutions in both the objective and the variable space. This is unlike most which consider diversity of solutions solely in the objective space. The performance of the algorithm is illustrated using a frigate design problem with an aim to minimise the building cost.

A model for the pressure drop in upward vertical core-annular flow is proposed. The model depends on two parameters that can be either adjusted to fit pressure drop data in cases when the behaviour of the pipe wall cannot be predicted or set to theoretical values for smooth and clean pipes. The physical basis for the model is the observation that the pressure drop in core-annular flow in comparable to the annulus fluid (usually water) alone in the pipe at mixture flow rate. Accordingly a two-phase multiplier is developed that accounts for the slip between the two phases and the physical properties of the two fluids.

The environmental performance of different double-hull tanker designs is evaluated using probabilistic oil outflow methodology proposed by IMO. Optimum positions for longitudinal and transverse bulkheads and ballast tanks are proposed to minimise oil outflow. Post-impact oil losses and retention in the double-hull space are considered as well as tidal drip and dynamic effects. Parametric studies are carried out for the influence of internal subdivision on the environmental performance of double-hulls in a series of collision and grounding situations. It is concluded that double-hull tankers will have fewer oil-spill accidents than single-hull ones and that larger tankers are safer for the environment.

Proposed ballast water standards published by the International Maritime Organization (IMO) as part of the 2004 Ballast Water Convention are considered here in light of data obtained from shipboard trials of various ballast water treatment (BWT) systems. Trials included taxonomic components for plankton beyond current IMO standards with particular focus on establishing criteria for phytoplankton. The large counting effort involved in establishing reliable counts for rare taxa suggested that a detailed taxonomic approach to standard setting was not practicable although an examination of dominant taxonomic groups seems feasible. Measurement of plankton sizes indicates that purely size-related IMO treatment standards may be problematic. These and other issues related to sample collection and processing for compliance testing are discussed.

The problem of estimating the quantity of oil spilled in the case of operational oil discharges from ships is considered. An evaluation of the spill observations on the Dutch Continental Shelf is given. Numbers of spillages and frequency of colours observed are analysed. Determining whether a spill is actually a violation is explored. The introduction of a new Bonn Agreement appearance code to estimate the quantity of oil spilled is examined. The accurate estimation from the air of the quantity of oil spillage is considered. Determining which operational spillages are combatable using a colour-appearance code is discussed. A number of alternatives to estimate the quantity of oil are considered and it is suggested to use the area polluted instead of the quantity spilled to determine the level of fine in the prosecution of potential oil polluters.

A new procedure for leak detection in fluid pipelines is presented. This procedure is based on the negative pressure wave detection method involving the use of special pressure drop algorithms. These algorithms enable the quick detection and identification of both the leak volume and pressure. Certain pressure drop algorithms are used to avoid false alarms and these are described. The exact function of the software that manages leak detection and location is detailed both in packed pipe sections and in slack-line areas. The presented pressure drop algorithms are realised as software modules for the integration into a SCADA system. The application software DFU and LEO work independently from other leak detection systems used at the pipeline. They are real-time systems implemented both in the substations along the pipeline and in the process control centre. The accuracy and response time is also considered.

Under UK law all substances used for treating oil spills in the marine environment must be approved. The approval process is described including elements of efficacy and risk assessment but with the focus primarily on the toxicity assessment. The main approval scheme includes two test procedures the sea and rocky shore tests against which all products are assessed. Both tests must be passed before an approval for use in UK waters can be granted. The sea test compares the toxicity of a standard oil (Kuwait crude) to the brown shrimp (Crangon crangon) under mechanical dispersion and in the same conditions after treatment with a candidate product. A product that significantly increases the toxicity of the untreated oil will fail the test. The rocky shore test simulates the exposure of a representative shore dweller the common limpet (Patella vulgata) to oil or product. In order to pass the test a product must not show greater toxicity than the oil. The toxicity test protocols are described in detail and the test validity and pass-fail criteria of each are explained. Further research issues are raised.